The present invention relates to a compressor and more particularly to a compressor that provides a suction and discharge mechanism, which is constituted of a valve plate, a suction valve and a discharge valve.
FIG. 2 shows a conventional swash plate type compressor around a suction and discharge mechanism. A valve plate 3 is interposed between a cylinder block 1 and a housing 2. The valve plate 3 forms a suction port 6 intercommunicating a cylinder bore 4 and a suction chamber 5, and a discharge port 8 intercommunicating the cylinder bore 4 and a discharge chamber 7. A suction valve 9 is disposed between the cylinder block 1 and the valve plate 3, and opens and closes the suction port 6. A discharge valve 10 is disposed between the housing 2 and the valve plate 3, and opens and closes the discharge port 8. An O-ring 11 is disposed between the cylinder block 1 and the housing 2.
According to the compressor constructed above, fluid in the suction chamber 5 is sucked into the cylinder bore 4 and is compressed and discharged to the discharge chamber 7 by reciprocation of a piston.
To achieve higher compression efficiency, sealing performance between the suction valve 9 and the valve plate 3 and between the discharge valve 10 and the valve plate 3 is required to improve. Alternative refrigerant gas such as carbon dioxide is promoted to be a practical use to deal with environmental problems these days. However, carbon dioxide for using in a compressor as refrigerant gas requires quite a high compression ratio. Therefore, the above-mentioned requirements for sealing performance have been further increasing these days.
The present invention addresses the above-mentioned problems traceable to a relatively high compression ratio by improving sealing performance between suction and discharge valves and valve plate.
A compressor has a first housing, a second housing, a valve plate, a suction valve, a discharge valve and a sealing coat. The first housing includes a compression chamber. The second housing includes a suction chamber and a discharge chamber. The valve plate is interposed between the first housing and the second housing. The suction valve is disposed between the first housing and the valve plate. The discharge valve is disposed between the second housing and the valve plate. The valve plate forms a suction port intercommunicating the suction chamber and the compression chamber, and a discharge port intercommunicating the discharge chamber and the compression chamber. The sealing coat made of soft metal is provided between the suction valve and the valve plate, and/or between the discharge valve and the valve plate.
The sealing coat made of soft metal inhibits refrigerant gas from leaking through any gap between the suction valve and the valve plate and between the discharge valve plate and the valve plate.
Other aspects and advantages of the invention will become apparent from the following description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.